kpk@gitpyr.UUCP (Kevin P. Kleinfelter) (01/29/86)
I have an interesting problem with my XT, and hope that the net can provide some suggestions as to how to proceed. The floppy drive on my XT occasionally refuses to read certain files. The error message varies, but occasionally includes "DRIVE NOT READY - CLOSE DOOR" etc. I wrote a program to read the file a sector at a time, and received no error. (i.e. The program asks DOS to read the next 512 bytes.) However, when the program asks DOS to read several sectors at once (i.e. a single DOS request for more than 512 bytes at once) the error occurs. I suspected timing problems, so I checked the drive's speed and found it accurate. I suspected alignment problems (as the files were written on another machine) but the disk works fine on other machines, and my computer reads the DOS master, Diagnostics, etc correctly (most of the time). Why would a single-sector read and a multi-sector read produce different results? (I can always just replace the drive, but I really am more interested in reason(s) and speculation(s) as to why.) Many thanks, kpk